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Cognitive Services : Translate Text into multiple languages using Asp.Net Core & C#


Introduction

In this article, we are going to learn how to translate text into multiple languages using one of the important Cognitive Services API called Microsoft Translate Text API ( One of the API in Language API ). It’s a simple cloud-based machine translation service and obviously we can test through simple Rest API call. Microsoft is using a new standard for high-quality AI-powered machine translations known as Neural Machine Translation (NMT).

Pic source : https://www.microsoft.com/en-us/translator/business/machine-translation/#whatmachine

You can also refer the following articles on Cognitive Service.

Prerequisites

  1. Subscription key ( Azure Portal ).
  2. Visual Studio 2015 or 2017

Translator Text API

First, we need to log into the Azure Portal with our Azure credentials. Then we need to create an Azure Translator Text API in the Azure portal. So please click on the “Create a resource” on the left top menu and search “Translator Text” in the search bar on the right side window or top of Azure Marketplace.

Click on the “create” button to create Translator Text API.

Provision a Translator Text Subscription Key

After clicking the “Create”, It will open another window. There we need to provide the basic information about Translator Text API.

Name : Name of the Translator Text API ( Eg. TranslatorTextApp ).

Subscription : We can select our Azure subscription for Translator Text  API creation.

Location : We can select our location of resource group. The best thing is we can choose a location closest to our customer.

Pricing tier : Select an appropriate pricing tier for our requirement.

Resource group : We can create a new resource group or choose from an existing one.

Now click on the “TranslatorTextApp” in dashboard page and it will redirect to the detailed page of  TranslatorTextApp ( “Overview” ). Here, we can see the “Keys” ( Subscription key details ) menu in the left side panel. Then click on the “Keys” menu and it will open the Subscription Keys details. We can use any of the subscription keys or regenerate the given key for text translation using Microsoft Translator Text API.

Language Request URL

The following request url gets the set of languages currently supported by other operations of the Microsoft Translator Text API.

https://api.cognitive.microsofttranslator.com/languages?api-version=3.0

Endpoint

The version of the API requested by the client and the Value must be 3.0 and also we can include query parameters and request header in the following endPoint used in our application.

https://api.cognitive.microsofttranslator.com/translate?api-version=3.0

Mandatory required parameters in the query string are “api-version” and “to” . The “api-version” value must be “3.0” as per the current documentation. “to” is the language code parameter used for translating the entered text into the desired language.

The mandatory request headers are “authorization header” and “Content-Type”. We can pass our subscription key into the “authorization header” and the simplest way is to pass our Azure secret key to the Translator service using request header “Ocp-Apim-Subscription-Key”.

 Index.html

The following html contains the binding methodology that we have used in our application by using the  latest Tag helpers of ASP.Net Core.

site.js

The following ajax call will trigger for each drop-down index change in the language selection using drop-down list.

// Write your JavaScript code.
$(function () {
    $(document)
        .on('change', '#ddlLangCode', function () {
            var languageCode = $(this).val();
            var enterText = $("#enterText").val();
            if (1 <= $("#enterText").val().trim().length && languageCode != "NA") {

                $('#enterText').removeClass('redBorder');

                var url = '/Home/Index';
                var dataToSend = { "LanguageCode": languageCode, "Text": enterText };
                dataType: "json",
                    $.ajax({
                        url: url,
                        data: dataToSend,
                        type: 'POST',
                        success: function (response) {
                            //update control on View
                            var result = JSON.parse(response);
                            var translatedText = result[0].translations[0].text;
                            $('#translatedText').val(translatedText);
                        }
                    })
            }
            else {
                $('#enterText').addClass('redBorder');
                $('#translatedText').val("");
            }
        });
});

Interface

The “ITranslateText” contains one signature for translating text content based on the given input. So we have injected this interface in the ASP.NET Core “Startup.cs” class as a “AddTransient”.

using System.Threading.Tasks;

namespace TranslateTextApp.Business_Layer.Interface
{
    interface ITranslateText
    {
        Task<string> Translate(string uri, string text, string key);
    }
}

Translator Text API Service

We can add the valid Translator Text API Subscription Key into the following code.

using Newtonsoft.Json;
using System;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using TranslateTextApp.Business_Layer.Interface;

namespace TranslateTextApp.Business_Layer
{
    public class TranslateTextService : ITranslateText
    {
        /// 
<summary>
        /// Translate the given text in to selected language.
        /// </summary>

        /// <param name="uri">Request uri</param>
        /// <param name="text">The text is given for translation</param>
        /// <param name="key">Subscription key</param>
        /// <returns></returns>
        public async Task<string> Translate(string uri, string text, string key)
        {
            System.Object[] body = new System.Object[] { new { Text = text } };
            var requestBody = JsonConvert.SerializeObject(body);
            
            using (var client = new HttpClient())
            using (var request = new HttpRequestMessage())
            {
                request.Method = HttpMethod.Post;
                request.RequestUri = new Uri(uri);
                request.Content = new StringContent(requestBody, Encoding.UTF8, "application/json");
                request.Headers.Add("Ocp-Apim-Subscription-Key", key);

                var response = await client.SendAsync(request);
                var responseBody = await response.Content.ReadAsStringAsync();
                dynamic result = JsonConvert.SerializeObject(JsonConvert.DeserializeObject(responseBody), Formatting.Indented);
                
                return result;
            }
        }
    }
}

API Response – Based on the given text

The successful json response.

[
  {
    "detectedLanguage": {
      "language": "en",
      "score": 1.0
    },
    "translations": [
      {
        "text": "सफलता का कोई शार्टकट नहीं होता",
        "to": "hi"
      }
    ]
  }
]

Download

Output

The given text is translated into desired  language listed in a drop-down list using Microsoft Translator API.

 

Reference

See Also

You can download other source codes from MSDN Code, using the link, mentioned below.

Summary

From this article we have learned translate a text(typed in english) in to different languages as per the API documentation using one of the important Cognitive Services API ( Translator Text API is a part of Language API ). I hope this article is useful for all Azure Cognitive Services API beginners.

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Cognitive Services : Extract handwritten text from an image using Computer Vision API With ASP.NET Core & C#


Introduction

In this article, we are going to learn how to extract handwritten text from an image using one of the important Cognitive Services API called Computer Vision API. So, we need a valid subscription key for accessing this feature. So before reading this article, you must read our previous articles related to Computer Vision API because we have explained other features of Computer Vision API in our previous article. This technology is currently in preview and is only available for English text.

Before reading this article, you must read the articles given below for Computer Vision API Knowledge.

Prerequisites

  1. Subscription key ( Azure Portal ).
  2. Visual Studio 2015 or 2017

Subscription Key Free Trail

If you don’t have Microsoft Azure Subscription and want to test the Computer Vision API because it requires a valid Subscription key for processing the image information. Don’t worry !! Microsoft gives a 7 day trial Subscription Key ( Click here ). We can use that Subscription key for testing purposes. If you sign up using the Computer Vision free trial, then your subscription keys are valid for the westcentral region (https://westcentralus.api.cognitive.microsoft.com ).

Requirements

These are the major requirements mentioned in the Microsoft docs.

  1. Supported input methods: Raw image binary in the form of an application/octet stream or image URL.
  2. Supported image formats: JPEG, PNG, BMP.
  3. Image file size: Less than 4 MB.
  4. Image dimensions must be at least 40 x 40, at most 3200 x 3200.

Computer Vision API

First, we need to log into the Azure Portal with our Azure credentials. Then we need to create an Azure Computer Vision Subscription Key in the Azure portal.

Click on “Create a resource” on the left side menu and it will open an “Azure Marketplace”. There, we can see the list of services. Click “AI + Machine Learning” then click on the “Computer Vision”.

Provision a Computer Vision Subscription Key

After clicking the “Computer Vision”, It will open another section. There, we need to provide the basic information about Computer Vision API.

Name : Name of the Computer Vision API ( Eg. HandwrittenApp ).

Subscription : We can select our Azure subscription for Computer Vision API creation.

Location : We can select our location of resource group. The best thing is we can choose a location closest to our customer.

Pricing tier : Select an appropriate pricing tier for our requirement.

Resource group : We can create a new resource group or choose from an existing one.

Now click on the “HandwrittenApp” in dashboard page and it will redirect to the details page of HandwrittenApp ( “Overview” ). Here, we can see the Manage Key ( Subscription key details ) & Endpoint details. Click on the “Show access keys…” links and it will redirect to another page.

We can use any of the subscription keys or regenerate the given key for getting image information using Computer Vision API.

Endpoint

As we mentioned above the location is the same for all the free trial Subscription Keys. In Azure we can choose available locations while creating a Computer Vision API. We have used the following endpoint in our code.

https://westus.api.cognitive.microsoft.com/vision/v1.0/recognizeText

View Model

The following model contains the API image response information.

using System.Collections.Generic;

namespace HandwrittenTextApp.Models
{
public class Word
{
public List<int> boundingBox { get; set; }
public string text { get; set; }
}

public class Line
{
public List<int> boundingBox { get; set; }
public string text { get; set; }
public List<Word> words { get; set; }
}

public class RecognitionResult
{
public List<Line> lines { get; set; }
}

public class ImageInfoViewModel
{
public string status { get; set; }
public RecognitionResult recognitionResult { get; set; }
}
}

Request URL

We can add additional parameters or request parameters ( optional ) in our API “endPoint” and it will provide more information for the given image.

https://westus.api.cognitive.microsoft.com/vision/v1.0/recognizeText%5B?mode%5D

Request parameters

These are the following optional parameters available in Computer Vision API.

  1. mode

mode

The mode will be different for different versions of Vision API. So don’t get confused while we are using Version v1 that is given in our Azure portal. If this parameter is set to “Printed”, printed text recognition is performed. If “Handwritten” is specified, handwriting recognition is performed. (Note: This parameter is case sensitive.) This is a required parameter and cannot be empty.

Interface

The “IVisionApiService” contains two signatures for processing or extracting handwritten content in an image. So we have injected this interface in the ASP.NET Core “Startup.cs” class as a “AddTransient”.

using System.Threading.Tasks;

namespace HandwrittenTextApp.Business_Layer.Interface
{
interface IVisionApiService
{
Task<string> ReadHandwrittenText();
byte[] GetImageAsByteArray(string imageFilePath);
}
}

Vision API Service

The following code will process and generate image information using Computer Vision API and its response is mapped into the “ImageInfoViewModel”. We can add the valid Computer Vision API Subscription Key into the following code.

using HandwrittenTextApp.Business_Layer.Interface;
using HandwrittenTextApp.Models;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Threading.Tasks;

namespace HandwrittenTextApp.Business_Layer
{
public class VisionApiService : IVisionApiService
{
// Replace <Subscription Key> with your valid subscription key.
const string subscriptionKey = "<Subscription Key>";

// You must use the same region in your REST call as you used to
// get your subscription keys. The paid subscription keys you will get
// it from microsoft azure portal.
// Free trial subscription keys are generated in the westcentralus region.
// If you use a free trial subscription key, you shouldn't need to change
// this region.
const string endPoint =
"https://westus.api.cognitive.microsoft.com/vision/v1.0/recognizeText";

///
<summary>
/// Gets the handwritten text from the specified image file by using
/// the Computer Vision REST API.
/// </summary>

/// <param name="imageFilePath">The image file with handwritten text.</param>
public async Task<string> ReadHandwrittenText()
{
string imageFilePath = @"C:\Users\rajeesh.raveendran\Desktop\vaisakh.jpg";
var errors = new List<string>();
ImageInfoViewModel responeData = new ImageInfoViewModel();
string extractedResult = "";
try
{
HttpClient client = new HttpClient();

// Request headers.
client.DefaultRequestHeaders.Add(
"Ocp-Apim-Subscription-Key", subscriptionKey);

// Request parameter.
// Note: The request parameter changed for APIv2.
// For APIv1, it is "handwriting=true".
string requestParameters = "mode=Handwritten";

// Assemble the URI for the REST API Call.
string uri = endPoint + "?" + requestParameters;

HttpResponseMessage response;

// Two REST API calls are required to extract handwritten text.
// One call to submit the image for processing, the other call
// to retrieve the text found in the image.
// operationLocation stores the REST API location to call to
// retrieve the text.
string operationLocation;

// Request body.
// Posts a locally stored JPEG image.
byte[] byteData = GetImageAsByteArray(imageFilePath);

using (ByteArrayContent content = new ByteArrayContent(byteData))
{
// This example uses content type "application/octet-stream".
// The other content types you can use are "application/json"
// and "multipart/form-data".
content.Headers.ContentType =
new MediaTypeHeaderValue("application/octet-stream");

// The first REST call starts the async process to analyze the
// written text in the image.
response = await client.PostAsync(uri, content);
}

// The response contains the URI to retrieve the result of the process.
if (response.IsSuccessStatusCode)
operationLocation =
response.Headers.GetValues("Operation-Location").FirstOrDefault();
else
{
// Display the JSON error data.
string errorString = await response.Content.ReadAsStringAsync();
//Console.WriteLine("\n\nResponse:\n{0}\n",
// JToken.Parse(errorString).ToString());
return errorString;
}

// The second REST call retrieves the text written in the image.
//
// Note: The response may not be immediately available. Handwriting
// recognition is an async operation that can take a variable amount
// of time depending on the length of the handwritten text. You may
// need to wait or retry this operation.
//
// This example checks once per second for ten seconds.
string result;
int i = 0;
do
{
System.Threading.Thread.Sleep(1000);
response = await client.GetAsync(operationLocation);
result = await response.Content.ReadAsStringAsync();
++i;
}
while (i < 10 && result.IndexOf("\"status\":\"Succeeded\"") == -1);

if (i == 10 && result.IndexOf("\"status\":\"Succeeded\"") == -1)
{
Console.WriteLine("\nTimeout error.\n");
return "Error";
}

//If it is success it will execute further process.
if (response.IsSuccessStatusCode)
{
// The JSON response mapped into respective view model.
responeData = JsonConvert.DeserializeObject<ImageInfoViewModel>(result,
new JsonSerializerSettings
{
NullValueHandling = NullValueHandling.Include,
Error = delegate (object sender, Newtonsoft.Json.Serialization.ErrorEventArgs earg)
{
errors.Add(earg.ErrorContext.Member.ToString());
earg.ErrorContext.Handled = true;
}
}
);

var linesCount = responeData.recognitionResult.lines.Count;
for (int j = 0; j < linesCount; j++)
{
var imageText = responeData.recognitionResult.lines[j].text;

extractedResult += imageText + Environment.NewLine;
}

}
}
catch (Exception e)
{
Console.WriteLine("\n" + e.Message);
}
return extractedResult;
}

///
<summary>
/// Returns the contents of the specified file as a byte array.
/// </summary>

/// <param name="imageFilePath">The image file to read.</param>
/// <returns>The byte array of the image data.</returns>
public byte[] GetImageAsByteArray(string imageFilePath)
{
using (FileStream fileStream =
new FileStream(imageFilePath, FileMode.Open, FileAccess.Read))
{
BinaryReader binaryReader = new BinaryReader(fileStream);
return binaryReader.ReadBytes((int)fileStream.Length);
}
}
}
}

API Response – Based on the given Image

The successful json response.

{
"status": "Succeeded",
"recognitionResult": {
"lines": [
{
"boundingBox": [
170,
34,
955,
31,
956,
78,
171,
81
],
"text": "Memories ! are born not made !",
"words": [
{
"boundingBox": [
158,
33,
378,
33,
373,
81,
153,
81
],
"text": "Memories"
},
{
"boundingBox": [
359,
33,
407,
33,
402,
81,
354,
81
],
"text": "!"
},
{
"boundingBox": [
407,
33,
508,
33,
503,
81,
402,
81
],
"text": "are"
},
{
"boundingBox": [
513,
33,
662,
33,
657,
81,
508,
81
],
"text": "born"
},
{
"boundingBox": [
676,
33,
786,
33,
781,
81,
671,
81
],
"text": "not"
},
{
"boundingBox": [
786,
33,
940,
33,
935,
81,
781,
81
],
"text": "made"
},
{
"boundingBox": [
926,
33,
974,
33,
969,
81,
921,
81
],
"text": "!"
}
]
},
{
"boundingBox": [
181,
121,
918,
112,
919,
175,
182,
184
],
"text": "Bloom of roses to my heart",
"words": [
{
"boundingBox": [
162,
123,
307,
121,
298,
185,
154,
187
],
"text": "Bloom"
},
{
"boundingBox": [
327,
120,
407,
119,
398,
183,
318,
185
],
"text": "of"
},
{
"boundingBox": [
422,
119,
572,
117,
563,
181,
413,
183
],
"text": "roses"
},
{
"boundingBox": [
577,
117,
647,
116,
638,
180,
568,
181
],
"text": "to"
},
{
"boundingBox": [
647,
116,
742,
115,
733,
179,
638,
180
],
"text": "my"
},
{
"boundingBox": [
757,
115,
927,
113,
918,
177,
748,
179
],
"text": "heart"
}
]
},
{
"boundingBox": [
190,
214,
922,
201,
923,
254,
191,
267
],
"text": "Sometimes lonely field as",
"words": [
{
"boundingBox": [
178,
213,
468,
209,
467,
263,
177,
267
],
"text": "Sometimes"
},
{
"boundingBox": [
486,
209,
661,
206,
660,
260,
485,
263
],
"text": "lonely"
},
{
"boundingBox": [
675,
206,
840,
203,
839,
257,
674,
260
],
"text": "field"
},
{
"boundingBox": [
850,
203,
932,
202,
931,
256,
848,
257
],
"text": "as"
}
]
},
{
"boundingBox": [
187,
304,
560,
292,
561,
342,
188,
354
],
"text": "sky kisses it",
"words": [
{
"boundingBox": [
173,
302,
288,
300,
288,
353,
173,
355
],
"text": "sky"
},
{
"boundingBox": [
288,
300,
488,
295,
488,
348,
288,
353
],
"text": "kisses"
},
{
"boundingBox": [
488,
295,
573,
293,
573,
346,
488,
348
],
"text": "it"
}
]
},
{
"boundingBox": [
191,
417,
976,
387,
979,
469,
194,
499
],
"text": "Three years iam gifted with",
"words": [
{
"boundingBox": [
173,
417,
324,
412,
318,
494,
167,
499
],
"text": "Three"
},
{
"boundingBox": [
343,
411,
504,
405,
498,
488,
337,
493
],
"text": "years"
},
{
"boundingBox": [
517,
405,
623,
401,
617,
483,
512,
487
],
"text": "iam"
},
{
"boundingBox": [
646,
400,
839,
394,
833,
476,
640,
483
],
"text": "gifted"
},
{
"boundingBox": [
839,
394,
977,
389,
971,
471,
833,
476
],
"text": "with"
}
]
},
{
"boundingBox": [
167,
492,
825,
472,
828,
551,
169,
572
],
"text": "gud friend happiness !",
"words": [
{
"boundingBox": [
159,
493,
274,
489,
274,
569,
159,
573
],
"text": "gud"
},
{
"boundingBox": [
284,
489,
484,
483,
484,
563,
284,
569
],
"text": "friend"
},
{
"boundingBox": [
504,
482,
814,
473,
814,
553,
504,
562
],
"text": "happiness"
},
{
"boundingBox": [
794,
474,
844,
472,
844,
552,
794,
554
],
"text": "!"
}
]
},
{
"boundingBox": [
167,
608,
390,
628,
387,
664,
163,
644
],
"text": "50870 W,",
"words": [
{
"boundingBox": [
159,
603,
321,
623,
310,
661,
147,
641
],
"text": "50870"
},
{
"boundingBox": [
309,
621,
409,
634,
397,
672,
297,
659
],
"text": "W,"
}
]
},
{
"boundingBox": [
419,
607,
896,
601,
897,
665,
420,
671
],
"text": "Seperation , sheds",
"words": [
{
"boundingBox": [
404,
609,
713,
604,
707,
669,
399,
674
],
"text": "Seperation"
},
{
"boundingBox": [
703,
604,
749,
604,
743,
669,
698,
669
],
"text": ","
},
{
"boundingBox": [
740,
604,
910,
602,
904,
667,
734,
669
],
"text": "sheds"
}
]
},
{
"boundingBox": [
161,
685,
437,
688,
436,
726,
160,
724
],
"text": "blood as in",
"words": [
{
"boundingBox": [
147,
687,
299,
684,
291,
726,
139,
729
],
"text": "blood"
},
{
"boundingBox": [
311,
683,
387,
682,
379,
724,
303,
725
],
"text": "as"
},
{
"boundingBox": [
398,
681,
440,
681,
432,
723,
390,
724
],
"text": "in"
}
]
},
{
"boundingBox": [
518,
678,
686,
679,
685,
719,
517,
718
],
"text": "tears !",
"words": [
{
"boundingBox": [
518,
677,
678,
682,
665,
723,
505,
717
],
"text": "tears"
},
{
"boundingBox": [
658,
681,
708,
683,
695,
724,
645,
722
],
"text": "!"
}
]
},
{
"boundingBox": [
165,
782,
901,
795,
900,
868,
164,
855
],
"text": "I can't bear it Especially",
"words": [
{
"boundingBox": [
145,
785,
191,
786,
184,
862,
138,
861
],
"text": "I"
},
{
"boundingBox": [
204,
786,
342,
787,
336,
863,
198,
862
],
"text": "can't"
},
{
"boundingBox": [
370,
788,
513,
789,
506,
865,
364,
864
],
"text": "bear"
},
{
"boundingBox": [
522,
789,
595,
790,
589,
866,
516,
865
],
"text": "it"
},
{
"boundingBox": [
605,
790,
913,
794,
907,
869,
598,
866
],
"text": "Especially"
}
]
},
{
"boundingBox": [
165,
874,
966,
884,
965,
942,
164,
933
],
"text": "final year a bunch of white",
"words": [
{
"boundingBox": [
155,
872,
306,
875,
294,
936,
143,
933
],
"text": "final"
},
{
"boundingBox": [
331,
876,
457,
878,
445,
939,
320,
936
],
"text": "year"
},
{
"boundingBox": [
466,
878,
508,
879,
496,
940,
454,
939
],
"text": "a"
},
{
"boundingBox": [
525,
879,
676,
882,
664,
943,
513,
940
],
"text": "bunch"
},
{
"boundingBox": [
697,
882,
772,
884,
760,
945,
685,
943
],
"text": "of"
},
{
"boundingBox": [
785,
884,
970,
888,
958,
948,
773,
945
],
"text": "white"
}
]
},
{
"boundingBox": [
174,
955,
936,
960,
935,
1006,
173,
1001
],
"text": "roses to me . I Loved it ! !",
"words": [
{
"boundingBox": [
164,
953,
348,
954,
341,
1002,
157,
1001
],
"text": "roses"
},
{
"boundingBox": [
376,
955,
445,
955,
437,
1003,
368,
1003
],
"text": "to"
},
{
"boundingBox": [
449,
955,
537,
956,
529,
1004,
442,
1003
],
"text": "me"
},
{
"boundingBox": [
518,
956,
564,
957,
557,
1005,
511,
1004
],
"text": "."
},
{
"boundingBox": [
569,
957,
615,
957,
607,
1005,
561,
1005
],
"text": "I"
},
{
"boundingBox": [
629,
957,
799,
959,
791,
1007,
621,
1005
],
"text": "Loved"
},
{
"boundingBox": [
817,
959,
886,
960,
879,
1008,
810,
1007
],
"text": "it"
},
{
"boundingBox": [
881,
960,
927,
960,
920,
1008,
874,
1008
],
"text": "!"
},
{
"boundingBox": [
909,
960,
955,
960,
948,
1008,
902,
1008
],
"text": "!"
}
]
},
{
"boundingBox": [
613,
1097,
680,
1050,
702,
1081,
635,
1129
],
"text": "by",
"words": [
{
"boundingBox": [
627,
1059,
683,
1059,
681,
1107,
625,
1107
],
"text": "by"
}
]
},
{
"boundingBox": [
320,
1182,
497,
1191,
495,
1234,
318,
1224
],
"text": "Vaisak",
"words": [
{
"boundingBox": [
309,
1183,
516,
1186,
492,
1229,
286,
1227
],
"text": "Vaisak"
}
]
},
{
"boundingBox": [
582,
1186,
964,
1216,
961,
1264,
578,
1234
],
"text": "Viswanathan",
"words": [
{
"boundingBox": [
574,
1186,
963,
1218,
945,
1265,
556,
1232
],
"text": "Viswanathan"
}
]
},
{
"boundingBox": [
289,
1271,
997,
1279,
996,
1364,
288,
1356
],
"text": "( Menonpara, Palakkad )",
"words": [
{
"boundingBox": [
274,
1264,
324,
1265,
306,
1357,
256,
1356
],
"text": "("
},
{
"boundingBox": [
329,
1265,
679,
1273,
661,
1364,
311,
1357
],
"text": "Menonpara,"
},
{
"boundingBox": [
669,
1273,
979,
1279,
961,
1371,
651,
1364
],
"text": "Palakkad"
},
{
"boundingBox": [
969,
1279,
1019,
1280,
1001,
1371,
951,
1370
],
"text": ")"
}
]
}
]
}
}

Download

Output

Handwritten content from an image using Computer Vision API. The content is extracted (around 99.99%) from the given image. If any failure occurs in detecting the image,it means that the Vision algorithm is not able to identify the written content.

Note : Thank you Vaisakh Viswanathan ( The author of the peom ).

Reference

See Also

You can download other ASP.NET Core source codes from MSDN Code, using the link, mentioned below.

Summary

From this article we have learned extract handwritten content from an image using One of the important Cognitive Services API ( Computer Vision API ). I hope this article is useful for all Azure Cognitive Services API beginners.

Cognitive Services – Optical Character Recognition (OCR) from an image using Computer Vision API And C#


Introduction

In our previous article we learned how to Analyze an Image Using Computer Vision API With ASP.Net Core & C#. In this article we are going to learn how to extract printed text also known as optical character recognition (OCR) from an image using one of the important Cognitive Services API called as Computer Vision API. So we need a valid subscription key for accessing this feature in an image.

Optical Character Recognition (OCR)

Optical Character Recognition (OCR) detects text in an image and extracts the recognized characters into a machine-usable character stream.

Prerequisites

  1. Subscription key ( Azure Portal ).
  2. Visual Studio 2015 or 2017

Subscription Key Free Trail

If you don’t have Microsoft Azure Subscription and want to test the Computer Vision API because it requires a valid Subscription key for processing the image information. Don’t worry !! Microsoft gives a 7 day trial Subscription Key ( Click here ). We can use that Subscription key for testing purposes. If you sign up using the Computer Vision free trial, then your subscription keys are valid for the westcentral region (https://westcentralus.api.cognitive.microsoft.com ).

Requirements

These are the major requirements mentioned in the Microsoft docs.

  1. Supported input methods: Raw image binary in the form of an application/octet stream or image URL.
  2. Supported image formats: JPEG, PNG, GIF, BMP.
  3. Image file size: Less than 4 MB.
  4. Image dimension: Greater than 50 x 50 pixels.

Computer Vision API

First, we need to log into the Azure Portal with our Azure credentials. Then we need to create an Azure Computer Vision Subscription Key in the Azure portal.

Click on “Create a resource” on the left side menu and it will open an “Azure Marketplace”. There, we can see the list of services. Click “AI + Machine Learning” then click on the “Computer Vision”.

Provision a Computer Vision Subscription Key

After clicking the “Computer Vision”, It will open another section. There, we need to provide the basic information about Computer Vision API.

Name : Name of the Computer Vision API ( Eg. OCRApp ).

Subscription : We can select our Azure subscription for Computer Vision API creation.

Location : We can select our location of resource group. The best thing is we can choose a location closest to our customer.

Pricing tier : Select an appropriate pricing tier for our requirement.

Resource group : We can create a new resource group or choose from an existing one.

Now click on the “OCRApp” in dashboard page and it will redirect to the details page of OCRApp ( “Overview” ). Here, we can see the Manage Key ( Subscription key details ) & Endpoint details. Click on the Show access keys links and it will redirect to another page.

We can use any of the subscription keys or regenerate the given key for getting image information using Computer Vision API.

 

Endpoint

As we mentioned above the location is the same for all the free trial Subscription Keys. In Azure we can choose available locations while creating a Computer Vision API. We have used the following endpoint in our code.

https://westus.api.cognitive.microsoft.com/vision/v1.0/ocr

View Model

The following model will contain the API image response information.

using System.Collections.Generic;

namespace OCRApp.Models
{
    public class Word
    {
        public string boundingBox { get; set; }
        public string text { get; set; }
    }

    public class Line
    {
        public string boundingBox { get; set; }
        public List<Word> words { get; set; }
    }

    public class Region
    {
        public string boundingBox { get; set; }
        public List<Line> lines { get; set; }
    }

    public class ImageInfoViewModel
    {
        public string language { get; set; }
        public string orientation { get; set; }
        public int textAngle { get; set; }
        public List<Region> regions { get; set; }
    }
}

Request URL

We can add additional parameters or request parameters ( optional ) in our API “endPoint” and it will provide more information for the given image.

https://[location].api.cognitive.microsoft.com/vision/v1.0/ocr[?language][&detectOrientation ]

Request parameters

These are the following optional parameters available in computer vision API.

  1. language
  2. detectOrientation

language

The service will detect 26 languages of the text in the image and It will contain “unk” as the default value. That means the service will auto detect the language of the text in the image.

The following are the supported language mention in the Microsoft API documentation.

  1. unk (AutoDetect)
  2. en (English)
  3. zh-Hans (ChineseSimplified)
  4. zh-Hant (ChineseTraditional)
  5. cs (Czech)
  6. da (Danish)
  7. nl (Dutch)
  8. fi (Finnish)
  9. fr (French)
  10. de (German)
  11. el (Greek)
  12. hu (Hungarian)
  13. it (Italian)
  14. ja (Japanese)
  15. ko (Korean)
  16. nb (Norwegian)
  17. pl (Polish)
  18. pt (Portuguese,
  19. ru (Russian)
  20. es (Spanish)
  21. sv (Swedish)
  22. tr (Turkish)
  23. ar (Arabic)
  24. ro (Romanian)
  25. sr-Cyrl (SerbianCyrillic)
  26. sr-Latn (SerbianLatin)
  27. sk (Slovak)

detectOrientation

This will detect the text orientation in the image, for this feature we need to add detectOrientation=true in the service url  or Request url as we discussed earlier.

Vision API Service

The following code will process and generate image information using Computer Vision API and its response is mapped into the “ImageInfoViewModel”. We can add the valid Computer Vision API Subscription Key into the following code.

using Newtonsoft.Json;
using OCRApp.Models;
using System;
using System.Collections.Generic;
using System.IO;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Threading.Tasks;

namespace OCRApp.Business_Layer
{
    public class VisionApiService
    {
        // Replace <Subscription Key> with your valid subscription key.
        const string subscriptionKey = "<Subscription Key>";

        // You must use the same region in your REST call as you used to
        // get your subscription keys. The paid subscription keys you will get
        // it from microsoft azure portal.
        // Free trial subscription keys are generated in the westcentralus region.
        // If you use a free trial subscription key, you shouldn't need to change
        // this region.
        const string endPoint =
            "https://westus.api.cognitive.microsoft.com/vision/v1.0/ocr";

        /// 
<summary>
        /// Gets the text visible in the specified image file by using
        /// the Computer Vision REST API.
        /// </summary>

        public async Task<string> MakeOCRRequest()
        {
            string imageFilePath = @"C:\Users\rajeesh.raveendran\Desktop\bill.jpg";
            var errors = new List<string>();
            string extractedResult = "";
            ImageInfoViewModel responeData = new ImageInfoViewModel();

            try
            {
                HttpClient client = new HttpClient();

                // Request headers.
                client.DefaultRequestHeaders.Add(
                    "Ocp-Apim-Subscription-Key", subscriptionKey);

                // Request parameters.
                string requestParameters = "language=unk&detectOrientation=true";

                // Assemble the URI for the REST API Call.
                string uri = endPoint + "?" + requestParameters;

                HttpResponseMessage response;

                // Request body. Posts a locally stored JPEG image.
                byte[] byteData = GetImageAsByteArray(imageFilePath);

                using (ByteArrayContent content = new ByteArrayContent(byteData))
                {
                    // This example uses content type "application/octet-stream".
                    // The other content types you can use are "application/json"
                    // and "multipart/form-data".
                    content.Headers.ContentType =
                        new MediaTypeHeaderValue("application/octet-stream");

                    // Make the REST API call.
                    response = await client.PostAsync(uri, content);
                }

                // Get the JSON response.
                string result = await response.Content.ReadAsStringAsync();

                //If it is success it will execute further process.
                if (response.IsSuccessStatusCode)
                {
                    // The JSON response mapped into respective view model.
                    responeData = JsonConvert.DeserializeObject<ImageInfoViewModel>(result,
                        new JsonSerializerSettings
                        {
                            NullValueHandling = NullValueHandling.Include,
                            Error = delegate (object sender, Newtonsoft.Json.Serialization.ErrorEventArgs earg)
                            {
                                errors.Add(earg.ErrorContext.Member.ToString());
                                earg.ErrorContext.Handled = true;
                            }
                        }
                    );

                    var linesCount = responeData.regions[0].lines.Count;
                    for (int i = 0; i < linesCount; i++)
                    {
                        var wordsCount = responeData.regions[0].lines[i].words.Count;
                        for (int j = 0; j < wordsCount; j++)
                        {
                            //Appending all the lines content into one.
                            extractedResult += responeData.regions[0].lines[i].words[j].text + " ";
                        }
                        extractedResult += Environment.NewLine;
                    }

                }
            }
            catch (Exception e)
            {
                Console.WriteLine("\n" + e.Message);
            }
            return extractedResult;
        }

        /// 
<summary>
        /// Returns the contents of the specified file as a byte array.
        /// </summary>

        /// <param name="imageFilePath">The image file to read.</param>
        /// <returns>The byte array of the image data.</returns>
        static byte[] GetImageAsByteArray(string imageFilePath)
        {
            using (FileStream fileStream =
                new FileStream(imageFilePath, FileMode.Open, FileAccess.Read))
            {
                BinaryReader binaryReader = new BinaryReader(fileStream);
                return binaryReader.ReadBytes((int)fileStream.Length);
            }
        }
    }

}

API Response – Based on the given Image

The successful json response.

{
  "language": "en",
  "orientation": "Up",
  "textAngle": 0,
  "regions": [
    {
      "boundingBox": "306,69,292,206",
      "lines": [
        {
          "boundingBox": "306,69,292,24",
          "words": [
            {
              "boundingBox": "306,69,17,19",
              "text": "\"I"
            },
            {
              "boundingBox": "332,69,45,19",
              "text": "Will"
            },
            {
              "boundingBox": "385,69,88,24",
              "text": "Always"
            },
            {
              "boundingBox": "482,69,94,19",
              "text": "Choose"
            },
            {
              "boundingBox": "585,74,13,14",
              "text": "a"
            }
          ]
        },
        {
          "boundingBox": "329,100,246,24",
          "words": [
            {
              "boundingBox": "329,100,56,24",
              "text": "Lazy"
            },
            {
              "boundingBox": "394,100,85,19",
              "text": "Person"
            },
            {
              "boundingBox": "488,100,24,19",
              "text": "to"
            },
            {
              "boundingBox": "521,100,32,19",
              "text": "Do"
            },
            {
              "boundingBox": "562,105,13,14",
              "text": "a"
            }
          ]
        },
        {
          "boundingBox": "310,131,284,19",
          "words": [
            {
              "boundingBox": "310,131,95,19",
              "text": "Difficult"
            },
            {
              "boundingBox": "412,131,182,19",
              "text": "Job....Because"
            }
          ]
        },
        {
          "boundingBox": "326,162,252,24",
          "words": [
            {
              "boundingBox": "326,162,31,19",
              "text": "He"
            },
            {
              "boundingBox": "365,162,44,19",
              "text": "Will"
            },
            {
              "boundingBox": "420,162,52,19",
              "text": "Find"
            },
            {
              "boundingBox": "481,167,28,14",
              "text": "an"
            },
            {
              "boundingBox": "520,162,58,24",
              "text": "Easy"
            }
          ]
        },
        {
          "boundingBox": "366,193,170,24",
          "words": [
            {
              "boundingBox": "366,193,52,24",
              "text": "way"
            },
            {
              "boundingBox": "426,193,24,19",
              "text": "to"
            },
            {
              "boundingBox": "459,193,33,19",
              "text": "Do"
            },
            {
              "boundingBox": "501,193,35,19",
              "text": "It!\""
            }
          ]
        },
        {
          "boundingBox": "462,256,117,19",
          "words": [
            {
              "boundingBox": "462,256,37,19",
              "text": "Bill"
            },
            {
              "boundingBox": "509,256,70,19",
              "text": "Gates"
            }
          ]
        }
      ]
    }
  ]
}

Download

Output

Optical Character Recognition (OCR) from an image using Computer Vision API.

Reference

See Also

You can download other ASP.NET Core source codes from MSDN Code, using the link, mentioned below.

Summary

From this article we have learned Optical Character Recognition (OCR) from an image using One of the important Cognitive Services API ( Computer Vision API ). I hope this article is useful for all Azure Cognitive Services API beginners.

 

Cognitive Services : Analyze an Image Using Computer Vision API With ASP.Net Core & C#


Introduction

One of the important Cognitive Services API is Computer Vision API and it helps to access the advanced algorithms for processing images and returning valuable information. For example By uploading an image or specifying an image URL, Microsoft Computer Vision algorithms can analyze visual content in different ways based on inputs and user choices. So we will get various information about the given image. We need a valid subscription key for accessing this feature.

Prerequisites

  1. Subscription key ( Azure Portal ).
  2. Visual Studio 2015 or 2017

Subscription Key Free Trail

If you don’t have Microsoft Azure Subscription and want to test the Computer Vision API because it requires a valid Subscription key for processing the image information. Don’t worry !! Microsoft gives a 7 day’s trail Subscription Key ( Click here ) . We can use that Subscription key for testing purpose. If you sign up using the Computer Vision free trial, Then your subscription keys are valid for the westcentral region ( https://westcentralus.api.cognitive.microsoft.com )

Requirements

These are the major requirements mention in the Microsoft docs.

  1. Supported input methods: Raw image binary in the form of an application/octet stream or image URL.
  2. Supported image formats: JPEG, PNG, GIF, BMP.
  3. Image file size: Less than 4 MB.
  4. Image dimension: Greater than 50 x 50 pixels.

Computer Vision API

First, we need to log into the Azure Portal with our Azure credentials. Then we need to create an Azure Computer Vision Subscription Key in the Azure portal.

Click on “Create a resource” on the left side menu and it will open an “Azure Marketplace”. There, we can see the list of services. Click “AI + Machine Learning” then click on the “Computer Vision”.

Provision a Computer Vision Subscription Key

After clicking the “Computer Vision”, it will open another section. There, we need to provide the basic information about Computer Vision API.

Name : Name of the Computer Vision API.

Subscription : We can select our Azure subscription for Computer Vision API creation.

Location : We can select our location of resource group. The best thing is we can choose a location closest to our customer.

Pricing tier : Select an appropriate pricing tier for our requirement.

Resource group : We can create a new resource group or choose from an existing one.

Now click on the MenothVision in dashboard page and it will redirect to the details page of MenothVision ( “Overview” ). Here, we can see the Manage Key ( Subscription key details ) & Endpoint details. Click on the Show access keys links and it will redirect to another page.

We can use any of the Subscription key or Regenerate the given key for getting image information using Computer Vision API.

Endpoint

As we mentioned above the location is same for all the free trail Subscription Key. In Azure we can choose available locations while creating a Computer Vision API. The following Endpoint we have used in our code.

https://westus.api.cognitive.microsoft.com/vision/v1.0/analyze

View Model

The following model will contain the API image response information.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace VisionApiDemo.Models
{
public class Detail
{
public List<object> celebrities { get; set; }
}

public class Category
{
public string name { get; set; }
public double score { get; set; }
public Detail detail { get; set; }
}

public class Caption
{
public string text { get; set; }
public double confidence { get; set; }
}

public class Description
{
public List<string> tags { get; set; }
public List<Caption> captions { get; set; }
}

public class Color
{
public string dominantColorForeground { get; set; }
public string dominantColorBackground { get; set; }
public List<string> dominantColors { get; set; }
public string accentColor { get; set; }
public bool isBwImg { get; set; }
}

public class Metadata
{
public int height { get; set; }
public int width { get; set; }
public string format { get; set; }
}

public class ImageInfoViewModel
{
public List<Category> categories { get; set; }
public Description description { get; set; }
public Color color { get; set; }
public string requestId { get; set; }
public Metadata metadata { get; set; }
}
}

Request URL

We can add additional parameters or request parameters ( optional ) in our API “endPoint” and it will provide more information for the given image.

https://%5Blocation%5D.api.cognitive.microsoft.com/vision/v1.0/analyze%5B?visualFeatures%5D%5B&details%5D%5B&language%5D

Request parameters

Currently we can use 3 optional parameters.

  1. visualFeatures
  2. details
  3. language

visualFeatures

The name itself clearly mentions it returns Visual Features of the given image. If we add multiple values in a visualFeatures parameters then put a comma for each value. The following are the visualFeatures parameters in API.

  • Categories
  • Tags
  • Description
  • Faces
  • ImageType
  • Color
  • Adult

details

This parameter will return domain specific information whether it is Celebrities or Landmarks.

Celebrities : If the detected image is of a celebrity it identify the same.

Landmarks : If the detected image is of a landmark it identify the same.

language

The service will return recognition results in specified language. Default language is english.

Supported languages.

  • en – English, Default.
  • zh – Simplified Chinese

Vision API Service

The following code will process and generate image information using Computer Vision API and its response is mapped into the “ImageInfoViewModel”. We can add the valid Computer Vision API Subscription Key into the following code.

using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.IO;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Threading.Tasks;
using VisionApiDemo.Models;

namespace VisionApiDemo.Business_Layer
{
public class VisionApiService
{
const string subscriptionKey = "<Enter your subscriptionKey>";
const string endPoint =
"https://westus.api.cognitive.microsoft.com/vision/v1.0/analyze";

public async Task<ImageInfoViewModel> MakeAnalysisRequest()
{
string imageFilePath = @"C:\Users\Rajeesh.raveendran\Desktop\Rajeesh.jpg";
var errors = new List<string>();
ImageInfoViewModel responeData = new ImageInfoViewModel();
try
{
HttpClient client = new HttpClient();

// Request headers.
client.DefaultRequestHeaders.Add(
"Ocp-Apim-Subscription-Key", subscriptionKey);

// Request parameters. A third optional parameter is "details".
string requestParameters =
"visualFeatures=Categories,Description,Color";

// Assemble the URI for the REST API Call.
string uri = endPoint + "?" + requestParameters;

HttpResponseMessage response;

// Request body. Posts a locally stored JPEG image.
byte[] byteData = GetImageAsByteArray(imageFilePath);

using (ByteArrayContent content = new ByteArrayContent(byteData))
{
// This example uses content type "application/octet-stream".
// The other content types you can use are "application/json"
// and "multipart/form-data".
content.Headers.ContentType =
new MediaTypeHeaderValue("application/octet-stream");

// Make the REST API call.
response = await client.PostAsync(uri, content);
}

// Get the JSON response.
var result = await response.Content.ReadAsStringAsync();

if (response.IsSuccessStatusCode)
{

responeData = JsonConvert.DeserializeObject<ImageInfoViewModel>(result,
new JsonSerializerSettings
{
NullValueHandling = NullValueHandling.Include,
Error = delegate (object sender, Newtonsoft.Json.Serialization.ErrorEventArgs earg)
{
errors.Add(earg.ErrorContext.Member.ToString());
earg.ErrorContext.Handled = true;
}
}
);
}

}
catch (Exception e)
{
Console.WriteLine("\n" + e.Message);
}

return responeData;
}

static byte[] GetImageAsByteArray(string imageFilePath)
{
using (FileStream fileStream =
new FileStream(imageFilePath, FileMode.Open, FileAccess.Read))
{
BinaryReader binaryReader = new BinaryReader(fileStream);
return binaryReader.ReadBytes((int)fileStream.Length);
}
}
}
}

API Response – Based on the given Image

The successful json response.

{
"categories": [
{
"name": "people_group",
"score": 0.6171875,
"detail": {
"celebrities": []
}
},
{
"name": "people_many",
"score": 0.359375,
"detail": {
"celebrities": []
}
}
],
"description": {
"tags": [
"person",
"sitting",
"indoor",
"posing",
"group",
"people",
"man",
"photo",
"woman",
"child",
"front",
"young",
"table",
"cake",
"large",
"holding",
"standing",
"bench",
"room",
"blue"
],
"captions": [
{
"text": "a group of people sitting posing for the camera",
"confidence": 0.9833507086594954
}
]
},
"color": {
"dominantColorForeground": "White",
"dominantColorBackground": "White",
"dominantColors": [
"White",
"Black",
"Red"
],
"accentColor": "AD1E3E",
"isBwImg": false
},
"requestId": "89f21ccf-cb65-4107-8620-b920a03e5f03",
"metadata": {
"height": 346,
"width": 530,
"format": "Jpeg"
}
}

Download

Output

Image information captured using Computer Vision API.For demo purpose, I have taken only a few data even though you can get more information about the image.

Reference

See Also

You can download other ASP.NET Core source codes from MSDN Code, using the link, mentioned below.

Summary

From this article we have learned how to implement One of the important Cognitive Services API ( Computer Vision API ). I hope this article is useful for all Azure Cognitive Services API beginners.

Code First Migration – ASP.NET MVC 5 With EntityFrameWork & MySql


Introduction

We know how to use Code First Migration in SQL Server. But in most cases, a customer will think we can use it for the open source database. So that’s the reason we pick the “MySQL” database, and we can follow the same steps we follow in the “SQL” database. In this article, we are going to explain Code First Migration in ASP.NET MVC 5 with Entity FrameWork & MySQL.

Prerequisites

  1. MySQL Installer
  2. Download MySQL Workbench
  3. Visual Studio ( We are using Visual Studio 2017 Community Edition ).

Create a Web Application using MVC 5

Click on File -> New -> Project -> Visual C# -> Web -> ASP.Net Web Application ( .Net Framework ).

Click on “OK” then click on “MVC”.

Install EntityFramework & MySql Entity

Go to Visual Studio “Tools -> Nuget Package Manager -> Manage Nuget Packages for Solution” or Right click on your Web Application then click on “Manage Nuget Packages”.

EntityFramework

Search EntityFramework in the “Browse” Section.

MySql.Data.Entity

Search MySql.Data.Entity in the “Browse” Section.

Once we installed EntityFramework & MySql Entity in our application then it will generate a SQL and MySQL Provider inside the EntityFramework Section in Web.Config.

<entityFramework>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
<providers>
<provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
<provider invariantName="MySql.Data.MySqlClient" type="MySql.Data.MySqlClient.MySqlProviderServices, MySql.Data.Entity.EF6, Version=6.8.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d"></provider></providers>
</entityFramework>

Model Class

We just created a sample model class for demo purpose.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace WebAppWithMySql.Models
{
public class Student
{
public int Id { get; set; }

public string Name { get; set; }

public string Password { get; set; }
}
}

Creation of DBContext

Create a db context class in our application. The following dbcontext will point out our connection string in WebConfig.

using MySql.Data.Entity;
using System.Data.Entity;
using WebAppWithMySql.Models;

namespace WebAppWithMySql
{
[DbConfigurationType(typeof(MySqlEFConfiguration))]
public class WebAppContext : DbContext
{
public DbSet<Student> Products
{
get;
set;
}
public WebAppContext()
//Reference the name of your connection string ( WebAppCon )
: base("WebAppCon") { }
}
}

Connection String

We added the same connection string name that we added in the dbcontext class. The following connection string represents “MySql” Db.

<connectionStrings>
<add name="WebAppCon" providerName="MySql.Data.MySqlClient" connectionString="server=localhost;userid=root;password=rajeesh123;database=WebAppMySql;persistsecurityinfo=True" />
</connectionStrings>

Migration Steps

  1. Enable-Migrations – ( We need to enable the migration, only then can we do the EF Code First Migration ).
  2. Add-Migration IntialDb (migration name) – ( Add a migration name and run the command ).
  3. Update-Database -Verbose — if it is successful then we can see this message (Running Seed method).

Once Migration is done; then, we can see that the respective files are auto-generated under the “Migrations” folder.

OutPut

See Also

You can download other ASP.NET Core source codes from MSDN Code, using the link, mentioned below.

Summary

In this article, we are going to explain Code First Migration in ASP.NET MVC 5 with EntityFrameWork & MySql. I hope this article is useful for all Azure beginners.

Send Email Using ASP.NET Core 1.1 With MailKit In Visual Studio 2017


Introduction

We are familiar with Sending Email Using Asp.Net With C#. But today, we are going to teach you how to send email using ASP.NET Core 1.1 with MailKit. We can implement it in ASP.Net Core very easily as compared to the previous versions of ASP.NET.

Before reading this article, you must read the articles given below for ASP.NET Core knowledge.

MailKit

MailKit is a cross-platform mail client library built on top of MimeKit. That means we get all the mail sending libraries from MailKit, such as – Simple Mail Transfer Protocol (SMTP) etc.

Simple Mail Transfer Protocol (SMTP)

Simple Mail Transfer Protocol (SMTP) is a TCP/IP protocol used in sending and receiving e-mail. Most e-mail systems that send mail over the Internet use SMTP to send messages from one server to another.The messages can then be retrieved with an e-mail client using either POP or IMAP.

The following is a list of SMTP Server and Port Numbers.

Sl.No Mail Server SMTP Server( Host ) Port Number
1 Gmail smtp.gmail.com 587
2 Outlook smtp.live.com 587
3 Yahoo Mail smtp.mail.yahoo.com 465
4 Yahoo Mail Plus plus.smtp.mail.yahoo.com 465
5 Hotmail smtp.live.com 465
6 Office365.com smtp.office365.com 587
7 zoho Mail smtp.zoho.com 465

Assemblies Required

The following assemblies are required for sending email using ASP.NET Core with MailKit.

using MailKit.Net.Smtp;
using MimeKit;

Adding MailKit in Our Project

Go to “Tools -> NuGet Package Manager -> Manage Nuget Package for Solutions…” Then, search “MailKit”, Choose and Install the latest version “V1.12.0” in your application.

MailKit Installation

MailKit Installation

Project Structure

New .NET Core tooling is available in Visual Studio 2017 by default. In the Dependencies folder, every package tool has separate folder like MailKit saved into NuGet folder. If you have a client side tool like bower, then its dependencies are saved into it’s folder.

Project Structure ASP.NET Core 1.1

Project Structure ASP.NET Core 1.1

Code

The following code contains the mail sending code of ASP.NET Core.

using MailKit.Net.Smtp;
using MimeKit;
using System;

namespace EmailApplication
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                //From Address
                string FromAddress = "From Email Address";
                string FromAdressTitle = "Email from ASP.NET Core 1.1";
                //To Address
                string ToAddress = "To Email Address";
                string ToAdressTitle = "Microsoft ASP.NET Core";
                string Subject = "Hello World - Sending email using ASP.NET Core 1.1";
                string BodyContent = "ASP.NET Core was previously called ASP.NET 5. It was renamed in January 2016. It supports cross-platform frameworks ( Windows, Linux, Mac ) for building modern cloud-based internet-connected applications like IOT, web apps, and mobile back-end.";

                //Smtp Server
                string SmtpServer = "smtp.gmail.com";
                //Smtp Port Number
                int SmtpPortNumber = 587;

                var mimeMessage = new MimeMessage();
                mimeMessage.From.Add(new MailboxAddress(FromAdressTitle, FromAddress));
                mimeMessage.To.Add(new MailboxAddress(ToAdressTitle, ToAddress));
                mimeMessage.Subject = Subject;
                mimeMessage.Body = new TextPart("plain")
                {
                    Text = BodyContent

                };

                using (var client = new SmtpClient())
                {

                    client.Connect(SmtpServer, SmtpPortNumber, false);
                    // Note: only needed if the SMTP server requires authentication
                    // Error 5.5.1 Authentication 
                    client.Authenticate("From Address Email", "Password");
                    client.Send(mimeMessage);
                    Console.WriteLine("The mail has been sent successfully !!");
                    Console.ReadLine();
                    client.Disconnect(true);

                }
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
    }
}

Important Points

  • When you are sending mail with your “gmail” account, enable less secure apps so that you will be able to login from all apps. Otherwise, it will throw authentication error like 5.5.1 authentication.
  • Remove 2-Step Verification.

In the following code, we can mention username for “gmail” account but in other service like “hotmail”, we must provide the full email address because other Microsoft accounts, like Outlook, live, etc. have the same SMTP Server Address “smtp.live.com”.

client.Authenticate("From Address Email", "Password");

csproj

In previous version, ASP.NET Core 1.0 contained all the versions & dependencies in project.json file but in new version, i.e., ASP.NET Core 1.1, they are saved in csproj.

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp1.1</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="MailKit" Version="1.12.0" />
  </ItemGroup>

</Project>

Output

References

Conclusion

We learned how to send email using ASP.NET Core 1.1 with MailKit in Visual Studio 2017. I hope, you liked this article. Please share your valuable suggestions and feedback.

Visual Studio 2017 : New Features & Installation


Introduction

Feeling great & Looking Smart. I know every one is excited for the new release of “Visual Studio 2017”. Yes , Microsoft Visual Studio celebrated it’s 20th years of glory with all tech lovers in the world love it. Now, it has come up with lots of excitement. Thus, I am happy to share the important features of Visual Studio 2017 with all the tech lovers.

Visual Studio 2017 System Requirements

The following are the minimum requirements of Visual Studio 2017 installation.

Download Visual Studio 2017

Go to this link Visual Studio 2017 , choose & download your favorite edition.

Installing Visual Studio 2017

Visual Studio 2017 Installation Window shows 3 sections.

  1. Workloads
  2. Individual components
  3. Language packs

Workloads

We can choose the appropriate development section from Visual Studio Workloads. I selected “ASP.NET and Web development & .NET Core cross-platform development”. It also contains around 5.50 GB. Thus, If you select all Workloads, then it will reach 50 GB+.

Individual components

We can choose the required component from this section.

Language packs

We can use different languages in Visual Studio. Thus, we can choose the appropriate language in this section.

Installation Process

We are going to install Visual Studio Community 2017 edition in our machine. Ones the following process is complete, we can launch & access the new features in Visual Studio 2017.

Features in Visual Studio 2017

The following are the new features in Visual Studio 2017.

Live Unit Testing

This feature is only available in Visual Studio 2017 Enterprise edition. Without running the solution, we can easily test the Application because few hidden background process happens in our Application through “Live Unit Testing”. We can enable Live Unit Testing for which you need to go to the “Test” command of the top-level menu bar in VS, choose “Live Unit Testing”, then “Start”.

Image Credit : Channel 9 Visual Studio 2017 Lanuch

Image Credit : Channel 9 Visual Studio 2017 Lanuch

We noticed that 3 symbols appeared in our code due to running on background Live Testing.

  • Cross Sign – line of executable code. The test is covered and it indicates that a failure test.
  • Tick Mark – line of executable code. The test is covered and it indicates that a success test.
  • Minus – line of executable code. Not yet covered a single Test.

Dotted Line

The is a very cool feature in Visual Studio 2017 because this option helps to identify the exact open and close curly braces “{}” through dotted line in our code. This dotted line is really helpful for when you are working on a bulk amount of code in a single page.

Filttered IntelliSense Search

The new Filtering IntelliSense Search option is available in Visual Studio 2017. This option is one of the powerful way to consume the search time in our code. The following IntelliSense bottom tray contains icons as Properties, Interface, Modules, Namespaces, Enums, Classes, Constants etc. For example, if i want to search an Interface, then I can choose an Interface Icon from the bottom of the tray, else it will show all the possible contents in our solution.

Improvements Of Navigation Controls

  1. Go to All ( Cntrl + T )
  2. Go to Line ( Cntrl + G )
  3. Go to File ( Cntrl + 1 + F )
  4. Go to Type ( Cntrl + 1 + T )
  5. Go to Member ( Cntrl + 1 + M )
  6. Go to Symbol ( Cntrl + 1 + S )

Go to All ( Cntrl + T )

Press “Cntrl + T”, then it will display one tray above the search bar. Thus, we can search the content with the help of the options given below like Line/Files/Types/Members/Symbols. For example, I want to search type in our entire solution or an Application. Now, choose “Type” Icon in the tray and type in the search bar, so it will filter and show the exact results as much as faster than the earlier versions of VS. The shortcut is “Cntrl + 1 + T”.

Find All Reference ( Shift + F12 )

We can find all the references in our entire solution. The highlighted one is all the reference results by a combination of project, definition and path.

Code Suggestions

This is a very exciting feature in VS2017. It gives us the good code practice in our Application. The code given below notices that we have written an “If” condition without curl braces. Thus, it gives us the suggestion tp add the curl braces to understand the code.

Code Style Changing

We can change the code style option in our VS2017. Go to “Tools -> Options -> Text Editor -> Basic -> Code Style -> Naming”.

Reference

Conclusion

We learnt installation & new features of Visual Studio 2017. I hope, you liked this article. Please share your valuable suggestions and feedback.

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